:root {
    --bg_color_01: #E0E0E0;
    --bg_color_02: #F9F9F9;
    --bg_color_03: #7E829F;
}

body {
  margin: 5;
  background-color: var(--bg_color_01); /* #e0e0e0; 01 */
  font-family: "Open Sans", Helvetica, Arial, sans-serif;
}

.fnb {
  background-color: var(--bg_color_01) /* #e0e0e0; 01 */
}

.pwidth {
  background-color: var(--bg_color_01) /* #e0e0e0; 01 */
  width: 80%;
  border: 15px;
  padding: 40px;
  margin: 10px;
}

ul {
  list-style-type: none;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background-color: var(--bg_color_03) /* #7e829f; 03   */
  font-size: 1.3em;                    /* 40px/16=2.5em */
}
 
li {
  float: left;
}

li a, .dropbtn {
  display: inline-block;
  color: black;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
  background-color: var(--bg_color_03) /* #7e829f; 03 */
}

li a:hover, .dropdown:hover .dropbtn {
  background-color: var(--bg_color_01) /* #e0e0e0; 01 */
}

li.dropdown {
  display: inline-block;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: var(--bg_color_02) /* #f9f9f9; 02 */
  min-width: 160px;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}

.dropdown-content a {
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
  text-align: left;
}

.dropdown-content a:hover {
  background-color: var(--bg_color_01) /* #e0e0e0; 01 */
}

.dropdown:hover .dropdown-content {
  display: block;
}

.title {
  font-size: 30px; /* 30px/16=1.875em */
}

.re_header {
  list-style-type: none;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background-color: var(--bg_color_03) /* #7e829f; 03   */
  font-size: 1.3em;                    /* 40px/16=2.5em */
}